Hair dryers, which are electric devices for drying an object, include a heater therein to heat air, and a fan motor for forcibly blowing the heated air, thereby conveniently drying a human hair or other wet objects. Thus, hair dryers are widely used for home and commercial purposes.
Such a hair dryer may include a brushless direct current (BLDC) motor that is a direct current (DC) motor having no brush and uses a semiconductor device to control current. Since BLDC motors do not require a brush, the service life thereof is long. In addition, since BLDC motors output high torque, they can rotate at high speed. Furthermore, since the control of current at a motor driver circuit is facilitated, speed of a BLDC motor can be efficiently controlled.
An example of such BLDC motors is disclosed in Korean Patent Registration No. 0935158, titled “ROTOR FAN COUPLING APPARATUS OF BLDC MOTOR FOR HAIR DRYER”, which has been filed by the present applicant and has been registered.
The BLDC motor includes: a fan main body including a plurality of rotor blades at a rotor fan part thereof; a rotor housing inserted in an inner surface of the fan main body; a rotor frame coupled to the fan main body, the rotor housing, and a rotation shaft; and a fan fixing spring fixedly connecting the fan main body and the rotor frame to each other. Accordingly, the rotor fan part is indirectly coupled to a motor part of the BLDC motor, and thus, the rotor fan part can be coupled and decoupled more easily and efficiently.
However, referring to FIG. 1, such a BLDC motor 20 for a hair dryer includes separately formed inner parts such as a bracket 400, a bearing housing 110, a printed circuit board (PCB) 300, and a stator 130. Thus, separate coupling members are required to assemble them. In addition, since most of parts are formed of metals, the total weight of the BLDC motor 20 is increased, and thus is inconvenient to use.
Furthermore, a sirocco fan installed on a shaft fan of a typical BLDC motor to forcibly blow air is coupled to a rotor housing through a pin, or is coupled to the central portion thereof, and thus, may be unstably rotated.